[PATCH v2] xfs_io: add support for O_TMPFILE opens
Christoph Hellwig
hch at infradead.org
Thu Feb 20 18:30:15 CST 2014
On Thu, Feb 20, 2014 at 02:00:00PM -0800, Christoph Hellwig wrote:
Add a new -T argument to the open command that supports using the
O_TMPFILE flag.
Signed-off-by: Christoph Hellwig <hch at lst.de>
---
Changes from V1:
- fix typo in the man page
- add -T option to the main option parser
- handle IO_TMPFILE in the file and stat commands
diff --git a/io/file.c b/io/file.c
index db85ffc..73b893f 100644
--- a/io/file.c
+++ b/io/file.c
@@ -36,7 +36,7 @@ print_fileio(
int index,
int braces)
{
- printf(_("%c%03d%c %-14s (%s,%s,%s,%s%s%s%s)\n"),
+ printf(_("%c%03d%c %-14s (%s,%s,%s,%s%s%s%s%s)\n"),
braces? '[' : ' ', index, braces? ']' : ' ', file->name,
file->flags & IO_FOREIGN ? _("foreign") : _("xfs"),
file->flags & IO_OSYNC ? _("sync") : _("non-sync"),
@@ -44,7 +44,8 @@ print_fileio(
file->flags & IO_READONLY ? _("read-only") : _("read-write"),
file->flags & IO_REALTIME ? _(",real-time") : "",
file->flags & IO_APPEND ? _(",append-only") : "",
- file->flags & IO_NONBLOCK ? _(",non-block") : "");
+ file->flags & IO_NONBLOCK ? _(",non-block") : "",
+ file->flags & IO_TMPFILE ? _(",tmpfile") : "");
}
int
diff --git a/io/init.c b/io/init.c
index ef9e4cb..fd1a52f 100644
--- a/io/init.c
+++ b/io/init.c
@@ -136,7 +136,7 @@ init(
pagesize = getpagesize();
gettimeofday(&stopwatch, NULL);
- while ((c = getopt(argc, argv, "ac:dFfmp:nrRstVx")) != EOF) {
+ while ((c = getopt(argc, argv, "ac:dFfmp:nrRstTVx")) != EOF) {
switch (c) {
case 'a':
flags |= IO_APPEND;
@@ -179,6 +179,8 @@ init(
case 'R':
flags |= IO_REALTIME;
break;
+ case 'T':
+ flags |= IO_TMPFILE;
case 'x':
expert = 1;
break;
diff --git a/io/io.h b/io/io.h
index 6c3f627..0d2d768 100644
--- a/io/io.h
+++ b/io/io.h
@@ -35,6 +35,7 @@
#define IO_TRUNC (1<<6)
#define IO_FOREIGN (1<<7)
#define IO_NONBLOCK (1<<8)
+#define IO_TMPFILE (1<<9)
/*
* Regular file I/O control
diff --git a/io/open.c b/io/open.c
index cc677e6..6bb0d46 100644
--- a/io/open.c
+++ b/io/open.c
@@ -22,6 +22,22 @@
#include "init.h"
#include "io.h"
+#ifndef __O_TMPFILE
+#if defined __alpha__
+#define __O_TMPFILE 0100000000
+#elif defined(__hppa__)
+#define __O_TMPFILE 040000000
+#elif defined(__sparc__)
+#define __O_TMPFILE 0x2000000
+#else
+#define __O_TMPFILE 020000000
+#endif
+#endif /* __O_TMPFILE */
+
+#ifndef O_TMPFILE
+#define O_TMPFILE (__O_TMPFILE | O_DIRECTORY)
+#endif
+
static cmdinfo_t open_cmd;
static cmdinfo_t stat_cmd;
static cmdinfo_t close_cmd;
@@ -77,13 +93,14 @@ stat_f(
int verbose = (argc == 2 && !strcmp(argv[1], "-v"));
printf(_("fd.path = \"%s\"\n"), file->name);
- printf(_("fd.flags = %s,%s,%s%s%s%s\n"),
+ printf(_("fd.flags = %s,%s,%s%s%s%s%s\n"),
file->flags & IO_OSYNC ? _("sync") : _("non-sync"),
file->flags & IO_DIRECT ? _("direct") : _("non-direct"),
file->flags & IO_READONLY ? _("read-only") : _("read-write"),
file->flags & IO_REALTIME ? _(",real-time") : "",
file->flags & IO_APPEND ? _(",append-only") : "",
- file->flags & IO_NONBLOCK ? _(",non-block") : "");
+ file->flags & IO_NONBLOCK ? _(",non-block") : "",
+ file->flags & IO_TMPFILE ? _(",tmpfile") : "");
if (fstat64(file->fd, &st) < 0) {
perror("fstat64");
} else {
@@ -143,10 +160,13 @@ openfile(
oflags |= O_TRUNC;
if (flags & IO_NONBLOCK)
oflags |= O_NONBLOCK;
+ if (flags & IO_TMPFILE)
+ oflags |= O_TMPFILE;
fd = open(path, oflags, mode);
if (fd < 0) {
- if ((errno == EISDIR) && (oflags & O_RDWR)) {
+ if (errno == EISDIR &&
+ ((oflags & (O_RDWR|O_TMPFILE)) == O_RDWR)) {
/* make it as if we asked for O_RDONLY & try again */
oflags &= ~O_RDWR;
oflags |= O_RDONLY;
@@ -248,6 +268,7 @@ open_help(void)
" -s -- open with O_SYNC\n"
" -t -- open with O_TRUNC (truncate the file to zero length if it exists)\n"
" -R -- mark the file as a realtime XFS file immediately after opening it\n"
+" -T -- open with O_TMPFILE (create a file not visible in the namespace)\n"
" Note1: usually read/write direct IO requests must be blocksize aligned;\n"
" some kernels, however, allow sectorsize alignment for direct IO.\n"
" Note2: the bmap for non-regular files can be obtained provided the file\n"
@@ -272,7 +293,7 @@ open_f(
return 0;
}
- while ((c = getopt(argc, argv, "FRacdfm:nrstx")) != EOF) {
+ while ((c = getopt(argc, argv, "FRTacdfm:nrstx")) != EOF) {
switch (c) {
case 'F':
/* Ignored / deprecated now, handled automatically */
@@ -310,6 +331,9 @@ open_f(
case 'x': /* backwards compatibility */
flags |= IO_REALTIME;
break;
+ case 'T':
+ flags |= IO_TMPFILE;
+ break;
default:
return command_usage(&open_cmd);
}
@@ -325,6 +349,11 @@ open_f(
if (!platform_test_xfs_fd(fd))
flags |= IO_FOREIGN;
+ if ((flags & (IO_READONLY|IO_TMPFILE)) == (IO_READONLY|IO_TMPFILE)) {
+ fprintf(stderr, _("-T and -r options are incompatible\n"));
+ return -1;
+ }
+
addfile(argv[optind], fd, &geometry, flags);
return 0;
}
@@ -731,7 +760,7 @@ open_init(void)
open_cmd.argmin = 0;
open_cmd.argmax = -1;
open_cmd.flags = CMD_NOMAP_OK | CMD_NOFILE_OK | CMD_FOREIGN_OK;
- open_cmd.args = _("[-acdrstx] [path]");
+ open_cmd.args = _("[-acdrstxT] [path]");
open_cmd.oneline = _("open the file specified by path");
open_cmd.help = open_help;
diff --git a/man/man8/xfs_io.8 b/man/man8/xfs_io.8
index 9543b20..7a92ff6 100644
--- a/man/man8/xfs_io.8
+++ b/man/man8/xfs_io.8
@@ -4,7 +4,7 @@ xfs_io \- debug the I/O path of an XFS filesystem
.SH SYNOPSIS
.B xfs_io
[
-.B \-adfmrRstx
+.B \-adfmrRstxT
] [
.B \-c
.I cmd
@@ -88,7 +88,7 @@ command for more details on any command.
Display a list of all open files and (optionally) switch to an alternate
current open file.
.TP
-.BI "open [[ \-acdfrstR ] " path " ]"
+.BI "open [[ \-acdfrstRT ] " path " ]"
Closes the current file, and opens the file specified by
.I path
instead. Without any arguments, displays statistics about the current
@@ -119,6 +119,14 @@ truncates on open (O_TRUNC).
.B \-n
opens in non-blocking mode if possible (O_NONBLOCK).
.TP
+.B \-T
+create a temporary file not linked into the filesystem namespace
+(O_TMPFILE). The pathname passed must refer to a directory which
+is treated as virtual parent for the newly created invisible file.
+Can not be used together with the
+.B \-r
+option.
+.TP
.B \-R
marks the file as a realtime XFS file after
opening it, if it is not already marked as such.
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